#include <iostream>
#include <cmath>
#define PI (3.14)
using namespace std;

int main()
{
    float h, r;
    cin >> h >> r;
    float v = PI * r * r * h / 1000; // v/L
    // printf("%f\n", v);

    int n = ceil(20 / v);

    printf("%d\n", n);

    return 0;
}